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heavy slow resistance

Dawid Łochyński, Dominik Kaczmarek, Włodzimierz Mrówczyński, Wojciech Warchoł, Joanna Majerczak, Janusz Karasiński, Michał Korostyński, Jerzy A Zoladz, Jan Celichowski
Dynamic resistance training increases the force and speed of muscle contraction, but little is known about modifications to the contractile properties of the main physiological types of motor units (MUs) that contribute to these muscle adaptations. Although the contractile profile of MU muscle fibers is tightly coupled to myosin heavy chain (MyHC) protein expression, it is not well understood if MyHC transition is a prerequisite for modifications to the contractile characteristics of MUs. In this study, we examined MU contractile properties, the mRNA expression of MyHC, parvalbumin, and sarcoendoplasmic reticulum Ca(2+) pump isoforms, as well as the MyHC protein content after 5 wk of volitional progressive weight-lifting training in the medial gastrocnemius muscle in rats...
October 1, 2016: Journal of Applied Physiology
Wataru Mizunoya, Shinpei Okamoto, Hideo Miyahara, Mariko Akahoshi, Takahiro Suzuki, Mai-Khoi Q Do, Hideaki Ohtsubo, Yusuke Komiya, Mulan Qahar, Toshiaki Waga, Koichi Nakazato, Yoshihide Ikeuchi, Judy E Anderson, Ryuichi Tatsumi
Our previous studies demonstrated that an 8-week intake of 5% (w/w) apple polyphenol (APP) in the diet improves muscle endurance of young-adult rats. In order to identify a lower limit of the dietary contribution of APP to the effect, the experiments were designed for lower-dose supplementation (8-week feeding of 0.5% APP in AIN-93G diet) to 12-week-old male Sprague-Dawley rats. Results clearly showed that the 0.5% APP diet significantly up-regulates slower myosin-heavy-chain (MyHC) isoform ratios (IIx and IIa relative to total MyHC) and myoglobin expression in lower hind-limb muscles examined (P < 0...
July 15, 2016: Animal Science Journal, Nihon Chikusan Gakkaihō
Jared Talbot, Lisa Maves
Skeletal muscle fibers are classified into fiber types, in particular, slow twitch versus fast twitch. Muscle fiber types are generally defined by the particular myosin heavy chain isoforms that they express, but many other components contribute to a fiber's physiological characteristics. Skeletal muscle fiber type can have a profound impact on muscle diseases, including certain muscular dystrophies and sarcopenia, the aging-induced loss of muscle mass and strength. These findings suggest that some muscle diseases may be treated by shifting fiber type characteristics either from slow to fast, or fast to slow phenotypes, depending on the disease...
July 2016: Wiley Interdisciplinary Reviews. Developmental Biology
Jon-Philippe K Hyatt, Lisa Nguyen, Allison E Hall, Ashley M Huber, Jessica C Kocan, Julie A Mattison, Rafael de Cabo, Jeannine R LaRocque, Robert J Talmadge
Shifts in myosin heavy chain (MHC) expression within skeletal muscle can be induced by a host of stimuli including, but not limited to, physical activity, alterations in neural activity, aging, and diet or obesity. Here, we hypothesized that both age and a long-term (2 year) high fat/high sugar diet (HFS) would induce a slow to fast MHC shift within the plantaris, soleus, and extensor digitorum longus (EDL) muscles from rhesus monkeys. Furthermore, we tested whether supplementation with resveratrol, a naturally occurring compound that has been attributed with augmenting aerobic potential through mitochondrial proliferation, would counteract any diet-induced MHC changes by promoting a fast to slow isoform switch...
2016: Frontiers in Physiology
Gerardo Puopolo, Selena Tomada, Paolo Sonego, Marco Moretto, Kristof Engelen, Michele Perazzolli, Ilaria Pertot
Lysobacter capsici AZ78 has considerable potential for biocontrol of phytopathogenic microorganisms. However, lack of information about genetic cues regarding its biological characteristics may slow down its exploitation as a biofungicide. In order to obtain a comprehensive overview of genetic features, the L. capsici AZ78 genome was sequenced, annotated and compared with the phylogenetically related pathogens Stenotrophomonas malthophilia K729a and Xanthomonas campestris pv. campestris ATCC 33913. Whole genome comparison, supported by functional analysis, indicated that L...
2016: Frontiers in Microbiology
Charles A Stuart, William L Stone, Mary E A Howell, Marianne F Brannon, H Kenton Hall, Andrew L Gibson, Michael H Stone
Muscle fiber composition correlates with insulin resistance, and exercise training can increase slow-twitch (type I) fibers and, thereby, mitigate diabetes risk. Human skeletal muscle is made up of three distinct fiber types, but muscle contains many more isoforms of myosin heavy and light chains, which are coded by 15 and 11 different genes, respectively. Laser capture microdissection techniques allow assessment of mRNA and protein content in individual fibers. We found that specific human fiber types contain different mixtures of myosin heavy and light chains...
March 1, 2016: American Journal of Physiology. Cell Physiology
Christian Giordano, Christian Lemaire, Tong Li, R John Kimoff, Basil J Petrof
BACKGROUND: Short-term intermittent hypoxia (IH) is common in patients with acute respiratory disorders. Although prolonged exposure to hypoxia induces atrophy and increased fatigability of skeletal muscle, the response to short-term IH is less well known. We hypothesized that the diaphragm and limb muscles would adapt differently to short-term IH given that hypoxia stimulates ventilation and triggers a superimposed exercise stimulus in the diaphragm. METHODS: We determined the structural, metabolic, and contractile properties of the mouse diaphragm after 4 days of IH (8 hours per day, 30 episodes per hour to a FiO2 nadir=6%), and compared responses in the diaphragm to a commonly studied reference limb muscle, the tibialis anterior...
2015: PloS One
Bernadett Kalmar, Gonzalo Blanco, Linda Greensmith
Skeletal muscles consist of muscle fibers that can differ in both composition and functional characteristics. These three types of muscle fibers, broadly categorized as slow, fast IIa, and fast IIb muscle fibers, express characteristic myosin heavy chain proteins and have different metabolic and enzymatic activities, which can be used as surrogate markers to identify the different fiber types. Pathological changes affecting the muscle, such as denervation, muscle disuse, and atrophy not only manifest on a functional level, but also as marked changes in the composition of muscle fiber type of individual muscles...
2012: Current Protocols in Mouse Biology
Rikke Beyer, Mads Kongsgaard, Birgitte Hougs Kjær, Tommy Øhlenschlæger, Michael Kjær, S Peter Magnusson
BACKGROUND: Previous studies have shown that eccentric training has a positive effect on Achilles tendinopathy, but few randomized controlled trials have compared it with other loading-based treatment regimens. PURPOSE: To evaluate the effectiveness of eccentric training (ECC) and heavy slow resistance training (HSR) among patients with midportion Achilles tendinopathy. STUDY DESIGN: Randomized controlled trial; Level of evidence, 1. METHODS: A total of 58 patients with chronic (>3 months) midportion Achilles tendinopathy were randomized to ECC or HSR for 12 weeks...
July 2015: American Journal of Sports Medicine
Alastair Khodabukus, Leslie M Baehr, Sue C Bodine, Keith Baar
The role of factors such as frequency, contraction duration and active time in the adaptation to chronic low-frequency electrical stimulation (CLFS) is widely disputed. In this study we explore the ability of contraction duration (0.6, 6, 60, and 600 sec) to induce a fast-to-slow shift in engineered muscle while using a stimulation frequency of 10 Hz and keeping active time constant at 60%. We found that all contraction durations induced similar slowing of time-to-peak tension. Despite similar increases in total myosin heavy (MHC) levels with stimulation, increasing contraction duration resulted in progressive decreases in total fast myosin...
October 2015: Journal of Cellular Physiology
William J Kraemer, David R Hooper, Tunde K Szivak, Brian R Kupchak, Courtenay Dunn-Lewis, Brett A Comstock, Shawn D Flanagan, David P Looney, Adam J Sterczala, William H DuPont, J Luke Pryor, Hiu-Ying Luk, Jesse Maladoungdock, Danielle McDermott, Jeff S Volek, Carl M Maresh
OBJECTIVE: This study evaluated whether a combination of whey protein (WP), calcium beta-hydroxy-beta-methylbutyrate (HMB), and carbohydrate exert additive effects on recovery from highly demanding resistance exercise. METHODS: Thirteen resistance-trained men (age: 22.6 ± 3.9 years; height: 175.3 ± 12.2 cm; weight: 86.2 ± 9.8 kg) completed a double-blinded, counterbalanced, within-group study. Subjects ingested EAS Recovery Protein (RP; EAS Sports Nutrition/Abbott Laboratories, Columbus, OH) or WP twice daily for 2 weeks prior to, during, and for 2 days following 3 consecutive days of intense resistance exercise...
2015: Journal of the American College of Nutrition
Suresh Sajwan, Roman Sidorov, Tereza Stašková, Anna Žaloudíková, Yoko Takasu, Dalibor Kodrík, Michal Zurovec
Adipokinetic hormones (Akhs) are small peptides (8-10 amino acid [aa] residues long) found in insects that regulate metabolic responses to stress by stimulating catabolic reactions and mobilizing energy stores. We employed Transcription activator-like effector nuclease (TALEN) mutagenesis and isolated an Akh(1) mutant carrying a small deletion in the gene that resulted in a truncated peptide; the second aa (Leu) was missing from the functional octapeptide. This null Dmel/Akh mutant is suitable to study Akh function without any effect on the C-terminal associated peptide encoded by the same gene...
June 2015: Insect Biochemistry and Molecular Biology
Nicholas L Reyes, Glen B Banks, Mark Tsang, Daciana Margineantu, Haiwei Gu, Danijel Djukovic, Jacky Chan, Michelle Torres, H Denny Liggitt, Dinesh K Hirenallur-S, David M Hockenbery, Daniel Raftery, Brian M Iritani
Mammalian skeletal muscle is broadly characterized by the presence of two distinct categories of muscle fibers called type I "red" slow twitch and type II "white" fast twitch, which display marked differences in contraction strength, metabolic strategies, and susceptibility to fatigue. The relative representation of each fiber type can have major influences on susceptibility to obesity, diabetes, and muscular dystrophies. However, the molecular factors controlling fiber type specification remain incompletely defined...
January 13, 2015: Proceedings of the National Academy of Sciences of the United States of America
Alastair Khodabukus, Keith Baar
Satellite cells derived from fast and slow muscles have been shown to adopt contractile and metabolic properties of their parent muscle. Mouse muscle shows less distinctive fiber-type profiles than rat or rabbit muscle. Therefore, in this study we sought to determine whether three-dimensional muscle constructs engineered from slow soleus (SOL) and fast tibialis anterior (TA) from mice would adopt the contractile and metabolic properties of their parent muscle. Time-to-peak tension (TPT) and half-relaxation time (1/2RT) was significantly slower in SOL constructs...
August 2015: Journal of Cellular Physiology
Ludmel Urdaneta-Marquez, Seong Han Bae, Patrick Janukavicius, Robin Beech, Joseph Dent, Roger Prichard
Heavy reliance on macrocyclic lactones to treat parasitic nematodes has resulted in the evolution of widespread drug resistance that threatens human and animal health. Management strategies have been proposed that would slow the rise of resistance, however testing these strategies has been hampered by the lack of identified strong-effect resistance markers in parasites. We show that the Caenorhabditis elegans gene Cel_dyf-7, necessary for amphid sensory neuron development, also confers macrocyclic lactone sensitivity...
December 2014: International Journal for Parasitology
Fuminori Kawabata, Takafumi Mizushige, Keisuke Uozumi, Kohsuke Hayamizu, Li Han, Tomoko Tsuji, Taro Kishida
In our previous study, fish protein was proven to reduce serum lipids and body fat accumulation by skeletal muscle hypertrophy and enhancing basal energy expenditure in rats. In the present study, we examined the precise effects of fish protein intake on different skeletal muscle fiber types and metabolic gene expression of the muscle. Fish protein increased fast-twitch muscle weight, reduced liver triglycerides and serum glucose levels, compared with the casein diet after 6 or 8 weeks of feeding. Furthermore, fish protein upregulated the gene expressions of a fast-twitch muscle-type marker and a glucose transporter in the muscle...
2015: Bioscience, Biotechnology, and Biochemistry
Alastair Khodabukus, Keith Baar
Skeletal muscle phenotype is regulated by a complex interaction between genetic, hormonal, and electrical inputs. However, because of the interrelatedness of these factors in vivo it is difficult to determine the importance of one over the other. Over the last 5 years, we have engineered skeletal muscles in the European Union (EU) and the United States (US) using the same clone of C2C12 cells. Strikingly, the dynamics of contraction of the muscles was dramatically different. Therefore, in this study we sought to determine whether the hormonal milieu (source of fetal bovine serum (FBS)) could alter engineered muscle phenotype...
December 2014: Journal of Cellular Biochemistry
Haiyan Zhao, Yoonju Kim, Joohyun Park, Daehun Park, Sang-Eun Lee, Iree Chang, Sunghoe Chang
Secretory carrier membrane protein 5 (SCAMP5), a recently identified candidate gene for autism, is brain specific and highly abundant in synaptic vesicles (SVs), but its function is currently unknown. Here, we found that knockdown (KD) of endogenous SCAMP5 by SCAMP5-specific shRNAs in cultured rat hippocampal neurons resulted in a reduction in total vesicle pool size as well as in recycling pool size, but the recycling/resting pool ratio was significantly increased. SCAMP5 KD slowed endocytosis after stimulation, but impaired it severely during strong stimulation...
July 23, 2014: Journal of Neuroscience: the Official Journal of the Society for Neuroscience
Jiang-Fei Meng, Teng-Fei Xu, Zhi-Zhen Wang, Yu-Lin Fang, Zhu-Mei Xi, Zhen-Wen Zhang
Grapes are an important economic crop and are widely cultivated around the world. Most grapes are grown in arid or semi-arid regions, and droughts take a heavy toll in grape and wine production areas. Developing effective drought-resistant cultivation measures is a priority for viticulture. Melatonin, an indoleamine, mediates many physiological processes in plants. Herein, we examined whether exogenously applied melatonin could improve the resistance of wine grape seedlings grown from cuttings to polyethylene glycol-induced water-deficient stress...
September 2014: Journal of Pineal Research
Stephen John Pearson, Syed Robiul Hussain
Patellar tendinopathy is a common painful musculoskeletal disorder with a very high prevalence in the athletic population that can severely limit or even end an athletic career. To date, the underlying pathophysiology leading to the condition remains poorly understood, although reports suggesting that patellar tendinopathy most frequently concerns the proximal posterior region of the tendon has prompted some researchers to examine region-specific tendon properties for a better understanding of the etiology and potential risk factors associated with the condition...
August 2014: Sports Medicine
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